Here is a fun way to make igloos with your students. You will need a couple bags of ice along with a few buckets of snow. Allow the students to create igloos with the ice cubes using the snow to hold the ice cubes together. You may want to have the students bring mittens or gloves to school on this day as their hands get quite cold. Take a picture of each child with his/her igloo as a keepsake. Have the students estimate how long it will take for their igloos to melt. Keep the igloos throughout the day so the students can observe how they change.